The anterior cruciate ligament is an important stabilizing structure of the knee joint, mainly including the anteromedial bundle and the posterior lateral bundle, some scholars also divide it into the middle bundle, which is morphologically and functionally close to the anteromedial bundle, therefore, the concept of double bundle is generally accepted. The anteromedial bundle is tense in flexion and plays a major role in anterior-posterior stability of the ACL, and the posterior lateral bundle is tense during knee extension and plays a major role in maintaining rotational stability of the knee joint . Once the ACL is broken, in addition to causing instability of the knee joint, it can also cause secondary damage to the meniscus and articular cartilage. Surgical reconstruction, especially arthroscopic ACL reconstruction, has become the main treatment for ACL ruptures. Traditional ACL reconstruction mostly performs a single-bundle reconstruction, i.e., reconstruction of the anteromedial bundle, and overall function is good, but the current literature reports rotational instability of the knee in more than 15% of patients after single-bundle reconstruction; therefore, a more anatomically correct double-bundle reconstruction of the ACL has emerged. Dual-bundle reconstruction requires 2 separate tunnels in the femur and tibia to introduce the graft, and it is sometimes difficult to create 2 tunnels in the tibia in particular, so some scholars have begun to investigate dual-bundle reconstruction of the ACL using a single tibial tunnel technique. Jin Hwan Ahn et al. at the Department of Orthopedics and Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, conducted a study to evaluate dual-bundle function after reconstruction and secondary arthroscopy to assess the association between morphology and function of the reconstructed ligament. In this retrospective study, secondary arthroscopy was performed in 37 cases after ACL double-bundle reconstruction and 62 cases without secondary arthroscopy after double-bundle reconstruction. 99 enrolled patients were followed up for 35 months (24-58 months), with a mean time from surgery to secondary arthroscopy of 25 months (12-36 months). Graft thickness, tension, and degree of synovial coverage were rated at the time of secondary arthroscopy. Correlations between graft morphology and Lysholm knee score, International Knee Documentation Committee (IKDC) grading, anterior laxity, and axial shift test results were sought. The results showed that 94 of 99 cases (94.9%) had an IKDC grading of B or better, with a mean anterior laxity of 1.29 mm (0-6 mm), and 92 knees had a negative axial shift test. In 37 patients with secondary arthroscopy, the anterior medial bundle was graded A in 28 (75.7%) and B in 9 (24.3%) according to graft thickness and tension. 25 (67.6%) of the posterior lateral bundles were graded A, 6 B, and 6 C. Based on the degree of synovial coverage, only 2 cases (5.4%) had a grade C anteroinferior bundle rating and 6 cases (16.2%) had a grade C postero-lateral bundle rating. There was no association between graft morphology and clinical outcome. The authors concluded that the same satisfactory results could be achieved with a single transtibial tunnel as with a double transtibial tunnel reconstruction. However, on secondary arthroscopy, more tears were found in the posterior lateral bundle than in the anterior medial bundle, and synovial coverage was low. There was no significant association between graft morphology and clinical outcome. Double-bundle reconstruction is a more physiologically correct anatomical reconstruction. The preparation of the tibial tunnel for the reconstruction of the anterior fork ligament with the currently used double-tunnel double-bundle reconstruction via the tibia requires a high level of skill, and a slight inadvertence may result in too much anterior displacement of the tunnel and thus affect the postoperative results. Therefore, many scholars reconstruct the anteromedial bundle first to ensure the function of the main part of the anterior fork ligament during the double-bundle reconstruction, and then reconstruct the posterior lateral bundle as appropriate. In some cases, a second tibial tunnel cannot be prepared after reconstruction of the anteromedial bundle and a single bundle reconstruction is performed instead. The authors of this article explored double-bundle reconstruction of the anterior fork ligament via a single tibial tunnel and compared it with a double-tunnel reconstruction group, and found that both groups had the same results, thus circumventing the clinical difficulties of double-tunnel tibial reconstruction and allowing more surgeons to perform double-bundle reconstruction for better functional rehabilitation. Preparation of the grafted tendon, AM for the anteromedial bundle and PL for the posterior lateral bundle Preparation of the femoral tunnel, with the anteromedial bundle tunnel located in the 1:30 direction and the posterior lateral tunnel located 5-7 mm above the medial edge of the posterior corner of the lateral meniscus at 90° of knee flexion, was performed with a single tibial tunnel double bundle reconstruction of the anterior fork ligament, with the caudal end of the tibial end tendon fixed to a cortical bone screw with a spacer. Secondary arthroscopic examination revealed good morphology of the anteromedial bundle and the posterior lateral bundle. Twenty-eight months after reconstruction, secondary arthroscopy showed good morphology of the anteromedial bundle and a partial tear of the posterior lateral bundle with poor synovial coverage.